Neptunium is a metal, it is not corrosive.
Neptunium is a chemical element, artificial, actinoid, transuranic, solid, metal, radioactive, able to support a nuclear fission and a nuclear chain reaction, with the atomic number 93, etc.
The name of the chemical element is derived from the name of the planet Neptune.
no
yes it is the most corrosive metal known to man due to its high charge density
Neptunium is an artificial element; in the nature neptunium is found in uranium ores, but is extremely rare.